Once dubbed the "Serengeti of Asia," almost all of Mondulkiri's wildlife was wiped out by poachers during decades of conflict, which began with the war in neighboring Vietnam. (See a Cambodia map.)

Now, with Cambodia finally at peace, small but growing populations of animals—including Indochinese tigers, Asian elephants, and critically endangered species such as the giant ibis—are returning to one of Southeast Asia's last remaining dry forests.

And Kha, now 45 years old, is helping to protect them as a head ranger supported by the international conservation group WWF.

"At the time I was ignorant and did not think there was a problem when I shot those tigers," he said, sitting at the forest headquarters in Mereuch as the Srepok River rushed behind him.

"Now I know we need to protect these animals for our children and grandchildren."

Coming Back Home

Humans cannot live inside the protected Mondulkiri Protected Forest reserve. A visitor can walk for miles without seeing any sign of humans, an unusual experience in otherwise densely populated Cambodia.

And with the region's searing summer temperatures and open, shadeless terrain, it's also usually hard to spot wildlife during the day.

But camera traps that take pictures at night show a different story.

A few years ago park rangers caught their first Indochinese tiger on camera. In 2007 a camera trap produced a picture of a female leopard and her cub.